Filter



Och-7, 1924. 1,510,568

E. J. SWEETLAND I FILTER Original Filed Feb. 2 1917 6 s -sh t 1 man".

3 alto m4 Qflhl M174 Oct. 7. l 924.

E. J. SWEETLAND FILTER na Filed Feb. 2. 1917 6 Sheets-Sheet 2 *IHIIIHHHHH A IN VE N TOR Oct. 7, 1924. 1,510,568

E. J. SWEETLAND v FILTE R Original Filed Feb. 2. 1917 6,Sheets-Sheet 5 Q W22 Q 2 0 ATTORNEY Oct. 7. 1924' J. SWE ETLAND FILTER s Sheets-Sheet Original Filed Feb. 2. 1917 INVENTOR W Mam "M O t, 7, 1924. f

E. .1. SWEETLAND FILTER 6 Sheets-Sheet 5 Original Filed Feb. 2. 1917 III-l I Q a 29 $9 *1 INVENTOR- I y a ATTOR EV Oct. 7. 1924. v 1,510,568

E. J. SWEETLAND FILTER Original Fil ed'Feb. 2. 1917 6 ShetS -Sheet e mvon ATTORNEY Essex,-

Paremea ea. 7, 1924.

UNHTED I S ES PATENT OFFICE. 1

ERNEST J. swEE'rLANn, or MONTICLA'VIR, NEW-JERSEY, assienoa "r0 UNITED FILTERS CORPORATION, OFN EW YORK, N. Y., A CORPORATION OF DELAWARE.

FILTER."

Original application filed-February 1917,. Seria1 No. 146,056. Divided and this application filed 7 January 34, 1919.

To all whom it may concern:

Be it known that L ERNns'r J. SWEET- LAND. a citizen of the: United" States, resid-' ing in the town of Montclair. county of and" State of New Jersey, have invented certain new and useful Improvements in Filters, of which the following is a. specification.

My invention relates broadly. to filters of the pressure type, that is filtersin which the material to be filtered is introduced into a closed compartment under pressure and'finds its'way' out by passing through filter cloth or other filter material, upon which the solids are deposited in the form of filtercake, while the clear liquid or filtrate is led away. Certainfeatures ofmy invention are partlcularly applicable to a type of filter in which the filter elements. or

filterfleaves are adapted to be moved relatively .to the casing or containing tank; preferably by being rotatable 'shaft which at once furnishes their support and also may act as a passage for the filtrate entering the leaves. My invention also a-ians'to provide in filtersof I this-rotary type an improved method of" sluicing in which a stream of wash Water.

' steannfor other cleansing agent' is-caused to travel across the face'of the rotating leaf, preferably by the rea'dy dislodgment of the filter cake adhering to the surfaceof the leaf.

Ialso provide certain improved features of construction for the container of pressure filters, such for instanceas the h nge and I I supply improved means for journaling the. central shaft or pipe upon which the filters of a rotary leaf type of filter are mounted in passing through the ends of the casing, so as1to avoid to the greatest-possible extent breakdown of the parts through wear while insuring a tight oint between the shaft or central'pipe and the section of proved means for 'peration and without substantial interferencewit-h the operation of the? other leaves.

' certain mounted upon a central,

automatic means, insuring I also provide im. 1 testing the output of any; individual leaf of a filter of the centrally: supported leaf type while the filter is in Serial No. 271,009.

become apparent in the course oft he ap- I pended description.

In the accompanying drawings which form a part of this application- Figure 1 is a side elevation, the parts being shownin central section for the purpose of clearness, of a filter embodying features of my invention.

:Figure 2 is an end elevation looking at the left-hand end of the filter of Figure 1.'

Figure 3 is afragmentary detail View, parts being shown in section, of a special type of hinge adapted foruse with this filter and the section .0 it is mounted. I

Figure tie .a vertical central sectional view of the type of filter illustrated in Figure 1, but. showing a different form of leaf construction, the 'view beingJtaken on a line corresponding to line IV-.IV of Figure 2. Figure 5 is a transverse sectional view on line V-.V of Figure 4; 4

Figure 6 is a transverse sectional view on line VI-V I of Figure 4. i Figure 7 is an elevation of the filter leaf shown'in Figure 1.- I 1 Figure 8 is an enlarged side view of the same leaf, parts being-shown in transverse central section. 'Figure 9 is a sectional View through the central plane of the leaf of Figure 8. Figure 10 is a side elevation of a portion of a 'leaf' and; the-supporting pipe, a porf the casing in which tion of the pipe being shown in central po'sifilter leaves and .sluicing pipes-together with associated parts.

Figure. 12 is a on line XII-XII of Figure -11.

transverse sectional view.

Figure13 is a detail view on an enlarged line XIII-XIIIof Figure 12.

scale on Figure 14 is a fragmentary top viewof a modified-form of sluicing nozzle, and

Figure 15 is a sectionalview of the same nozzle on line -XVXV of Figure 14:.

. Figure 16;is a central longitudinal sectionthrough a portion of the filter showing a 8 is an end view of the device of a Fi ure 17.

Figure 19 is an'end view of'a modified type of filter construction.

Figure '20 is a sectional view XX-XX of Figure 19. 1 Figure 21 is a plan view of a further modi fication;

Figures 22 and 23 are-end and side views "of a further modification, of which Figure on line 24 is a'fragmentary sectional view on an enwith a handle 22 and at the other with a larged scale.

Figure 25 shows a stil dilterent type of construction, and

Figure 26 is a fragmentary sectional view of the connection mtw'een the, leaf and the drainage pipe.

Referring to the drawings in detail. the numeral .1 designates posts or standards adapted to support the upper semi-cylindrical member 2 of the filter. The filter casing is completed bya lower semi-cylin drical member 3 which is preferably attached to the uppensection along one side by means of a. pluralityof hinges a. One leaf of each hinge is permanently secured to the lower section of the casing as by means of the boltsl5, and is provided with an upwardly extending lug or boss centrally drilled for the reception of the pintle 6. The other leaf-7 of each hinge is adjustably secured to the upper section of the. casing, 7 referably by means of an integral thread stud 8 passing through a lug 9 and having its upper end 10 provided with a suitable nut 11, b which the stud and pintle may be vertica 1y adjusted- This construction makes it possible to raise and lower the axis of the pintle of the hinge-as may be necessary owing to wear in the gasket (not shown) which provides a water-tight seal between the upper and the lower sec.- tions of the casing when they are clamped in operative position. w

Along the opposite side of the filter is disposed a plurality of swing bolts 12 attached to a cam shaft 13 and having their lower-extremities provided with nuts '14: and washers 15 adapted to engage lugs 16 pro-- jecting from the side of the lower section of the casing. A handle 17 is provided for turning the shaft 13 and thereby operating the swing bolts. The construction of the swing bolts and the cam; shaft upon which they are mounted, by means of which the bolts automatically are moved longitudinally and then are swung out of engagement with the lugs 16 by the rotation. of the shaft, is described and claimed inmy/United States Patent No. 1,08%;605 andwill not be here set 1 forth in detail, as they form no part of my the turning of the'h-andle 17 vertically downward until they are free from thelugs 16; and that further rotation of the handle'then swings them. to the r'i 'ht, out of engagement with the lugs, thus re easing that edge of the lower section of the casing from the upper section of the easing, except for an auxiliary clamp (see F ig.

1) consisting of links 18 pivot-ally secured at 19 ton lug 20 which may be v integral with the upper section of the casin lower ends of the links are'pivotally connected to a lever-21 provided at one end lockinga-rm 23 adapted to engage under the lower edge of thelug20,as shown in l, and thus clamp the upper and lower sec tions of the casing firmly together when the handle of the lever is pushed inwardly toward the filter hodv. To prevent the sud den dropping of the lhwe'r section of the easing' when the swing bolts and lockingdevice just described are released, I may provide the lower section of the casing with a counter-weight 2t mounted upon a curved arm 25 secured to the lower section of the casin in any suitable manner, as by means of be ts 26." This counter-weight is so proportioned that it just balancesthe weight of the lower section of the casing. The latter may thus be readily swung around the axis of the p'intle 60f the hinges either by hand or by other power means until it assumes a substantially vertical position. Jis stated above, suitable gas ets (not shown) are provided for maintaini (r a fluid-tight joint between the abuttin e ges' of the up per and lower sections of the casing.

- Centrally arranged with reference to the two filter seitionsis a longitudinal pipe 'or conduit 27 which is journaled at each end insuitable bearings 28. carried by the posts 1, the details ot'these bearings being shown in Figs, 1 and 4. The section of the pipe which passes through the casingis surrounded by with a stufling box 29 including the packing 30 arranged in the usual .manner so asto prevent leakage of liquid from the interior screw 34. is positioned at the outer flush surfaces of the flange 31, seat 32. and collar 28,

and thereby maintains the pipe 27 in proper, axial position during its periods of rotation Inn a collar 28 which is provided at its inner end llti This collar is mounted between the 1 and of rest by preventing its movement lonigitudinal'lyr A. circular strip of packing 35 lliltl for oiling the bearing maybe provided by i is mounted in a groove in the outer surface of the collar 28 between its stufiing box and the collar 33 in such position as to seat against the portion 36 of the lower section of the rasing, which is curved to fit and which contacts with the lower half of the collar 28 when the lower section of the easing is in normal operative position. Means an oil cup 37 or other suitable means leading through the seat- 32 and the collar 28. It will be seen that by this construction an absolutely fluid-tight jointmay be formed between the lower movable part of the -casing, the fixed upper section of the casing,

.and the rotatable shaft or pipe, at the point.

where the latter pierces the casing, since seepage of fluid between the collar 28 and the p pe is prevented by the'packing, 30 of the stufling box 29, while leakage along the outside ofthe collar 28 is prevented by the packing 35 which contacts both with the .upper section of the casing and with the lower section of the casing. At the same time there 'is.no tendencyjto abrade the packing 35, since .the'collar 28 is stationary 'within the casing and does not move with tached a central fittin the pipe 27. Consequently there is no wear between it and the lower section at 36, save simply that of compression when the lower section is clamped in place.

In the filter shown' in Fig. 1 the central pipe 27 is provided with a plurality of filter leaves 38, illustrated in detail in Figs. 7 to 10, inclusive. Each of these filter leaves consists of a plurality of-substantially semicircular sections 39, 40, joined at the end of a diameter by 'a hinge 41 and at the other bya suitable latch 42. Each half is preferably provided with a central drainage member 43 preferably formed of heavy screen, on each side of which is a layer of filter cloth 44, the cloth and the screen being clamped together by means of aperipheral ring '45 of U-shaped section. The ,flat edge of each half leaf is provided with abinding strip 46 of similar U-section, to which is at- 47 formed for engagement with the outslde of the pipe 27 and having a reeess 48 for the reception of a v nipple 49 leading from the interior of the pipe 27 and ro ecting a short distance 'beyond the sur ace of the pipe 27. A circular gasket 50 is provided adjacent to theouter end of each of thenipples 49, so that when the filter leaf is clamped in place a fluid- 1 tight joint is thus effected between the interior of the pipe 49 and the passage 51- which leads to the drainage area formed by the drainage member 43.

Wherithe fluid to be, filtered is introduced into the interior of the filter casing, as through the inlet manifold 52 (see Fig. 2),.

the onl. outlet for. such liquid is throu h the clot 44 ofthe filter leaves into the 1nj-terior or drainage area of each leaf formed inally held in suspension in the liquid to be filtered cannot pass through the cloth 44,

and is deposited on the outer surfacd of each leaf in the form of a layer of solid matter, which is known as the filter cake.

An alternative form ofleaf construction is shown in Figs. 4-, 5 and 6 in which each leaf 53, as before, may consist of a central drainage section formed of screen, covered by filter fabric, but each leaf has a continuous peripheral binding edge, so that it is integral and self contained. At the cepter the leaf is provided with a circular opening entirely through it and just large enough to receive the pipe 27 at its central portion, which is of slightly larger diameter than the end portions which pass through the hearings in the casing. On each side of each leaf is an annulargasket 54 having inwardly projecting tabs 54. en-

gaging the outer surface of thepipe 27 andv thus positioning the gasket upon it while suitablyspacingit from the pipe. Adjacent to the other face of each gasket is a separatoror spacingcollar 55 having substantially the same cross-section as the gasket, but

-The entire assembly 1s clamped in the pipeby meansof collars 58; and 59'having,in-'

A. plurality of ternal threads adapted to engage threads not shown)-formed on the outer surface of t e pipe at that point. Gaskets 59 may be provided for insuring a liquid-tight joint between the end or terminal filter leaves and the threaded collars. i

To wash the surfaces of the filter leaves when it is desired to free them from the deposit of filter cake that may be formed on- 5 '12 in detai in Figs. 2 and .11 to 15, inclusive.

them, I rovide the structure which is shown A sluicing man fold 60 passes through suitable stufiing boxes 61 at each end of, the casing and is provided with sluicing1 pipes 62 preferably entering between eac pair of filter leaves. These sluicing pipes may be provided with any preferred form of orifice for the-discharge of water, compressed air, steam, or other cleansing fluid, but I prefer to provide the end of each pipe with a nozzle 63, asshown in detail in Figs. 12. and 13. Each nozzle preferably consists of a fitting suitably secured to the end of the pipe, 62, as by being screwed thereon, and having a central passage 64 at right angles to the bore of the pipe 62. The ends of the fitting are preferably inclined as shown and are protected by some suitable form of, Va ve, such as a strip, 65 of thin resilient ma.-

terialsuch as spring steel, secured at one edge 66 to the fitting. .When fluid under pressure is admitted to the pipe 62- it passes sion in the liquid in the casing froin backing.

through it to the bore 64: of the nozzle-and readily pushing aside the valves 65, im-

pinges upon theadjacent surface of a filter leaf in a fiat cutting stream which is. substantially parallel to the surface of the-filter leaf. At times when nowash water or other fluid is introduced into the sluicing pipes. the flap valves 65 close the. orifices of the nozzles and preventsolid matter in suspenup into the'nozzles and clogging them 'and the pipes through which they are fed. In the filtration of .many materials, such as sugar refinery liquors, which'contain a considerable amount of foreign matter in susension, especially fibrous Substances, the.

I liquor backs up into the. sluicing pipe durthe periods when filtration is in progress, and often clogs up the nozzle. It willbe seen that with the construction just de-- scribedno sludge or liquid containing mat-1 ter in suspension can enter the nozzle or the sluicing pipe, and the greater the pressure under which the sludge is pumped into the filter, the greater the force causing the valve 65 to seat tightly against the orifice of the nozzle fitting '64. 11 alternative form of nozzle construction is shownin Figs. 14 and 15. I Tn thistype I propose to form the nozzle of ail-integral molded cap- 67 of rubber or other suitable material which maybe slipped over the outer end of the pipe 62 and may be held thereon byany suitable con-- strictive means such as wire 68, the ends of sever the end of the cap from the body of it, but whichleave's an integral tongue 70 I ber-to-rubber joint between connecting the end of the capwith the body portion, t us forming a flap 71 corresponding in its function to the flap 65 already de- 'scrlbed. This construction even more efiec-.

tually prevents backing up of solid-laden liquid into the nozzle, since thene is' a rub body of the nozzle. t 4

lln order to cause the nozzle of each of the flap and the nominee the 'sluicing pipes'to-sweep across the surface of the filter leaves as the latter revolve within the casin the manifold 60 is made protatable within its stu fling box supports, and the means illustrated in Figures 1 and2 are provided for-automatically gear 74:- kcyed to the shaft 75 carrying acam 76. This cam engages a cam follower 77 which-is secured to the manifold 60 and drives it. The follower is also provided with an extending arm 78 to which is con- Q nected a spring 79 fixed at its other endto a standard 80. This spring acts to keep I .the fbllower constantly in engagement wit thesurface of the cani and'to overcome any friction in the stuffing boxes. The can). s so designed as to cause a'slow advance of the nozzle from the position of Fig. l2

down across the. face of .the filter leaves, and then to produce a relatively quick return back to the initial position. it will be appreciated that thesluicing pipes do not cross the central pipe 27- but across only half of the face of each eaf, but-this is suficient since the leaves themselves are meanwhile rotated.

In Figs. '16, 17v and 18 it have illustrated a device for sampling the efiufent filtrate efficient operation of the other leaves. in some pressure filters having leaves as the shown in my United States lc'teissue Letters Patent No. 14,213. 'However,.with filters filter elements, .thi's efiect-is accomplished.

from any individual leaf without, halting the process of filtratipn or interrupting the 3 105 is cgmposed of glass.- Such'construction-is of the rotating; leaf type, this plan is 'obvi--- ously im racticableand some othermeans such as t at here illustrated. must be used erformance of the for determining the variousileavesj lit wil be appreciated that in the process of filtration, one of the leaves -may fail, thus causingithe filtratefiowing from the machine to become charged with solids that have entered the filtrate mani fold through theleaf which has broken down, or it may be that one of the leaves.

has become clo ged so asto prevent eficient filtration y it. For these reasons it is highly desirable to be able to test. at

anytlm'e the filtrate issuinr from an leaf. In the type .of device iflustrated 1n the drawings a spool-shaped member 100 .havingacupped; outer surface 101. and preferab y composed. of rubber or othersomewhat flexible r'esilientmaterial, is adapted to be introduced into the central drainage pipe 27.

met

This member is mounted onand supported by in a pipe 102, opening at each end into the annular space boundedby the cup-shaped sur-1 the adjacent portion of being disposed so as to be longitudinally arranged with reference tothe drainage member 27 when the device is inserted therein. In practice, the member 100-is inserted into the drainage member 27 until the cup-shaped member spans the drainage zone of any one leaf. For instance, in Fig. 16 the device is in position to samplev the filtrate flowing from leaf 10.4. The lips of the cup-shaped member 100 contact sufficientl tightly with the inner surface of the wal of the drainage member 2;7' to prevent seepage of the efliuent filtrate from the leaf 104 past the lips or edges of the member 100, so that the only outlet for this filtrate is through the pipe 102 and so on out through the pipe 103, which is made lon enoughto project beyond the open end of t e pipe 27, where it extends beyond the casin of the filter. that y the use of this device the] efiiuent filtrate from any leaf may be led separately out of the filter ,into a receptacle for observation or testing. In orderthat the operator may be able to aline the pipe 102 with sufficient accuracy with the drainage nip.- ples of thevarious filter leaves, the outer extending end 105 of the-pipe 103 may be provided with desi nating marks 106'such that when any mark isplaced in alinement with the end of the pipe .27, or.with any other predetermined fixedpoint on the filter body, the spool-shtaped member 100 will then be in proper position to draw the filtrate from the filter leaf whose'number corresponds withthatfon the indicia 106. [It will be observed that the pipe 102 and member'100 do not block the nterior-of pipe liquid being 27 to suchan extent as to prevent the ready flow of filtrate from other'filterleaves past them and so on outof .thefilter. in the normal wag. p

InFigures 19 and 20 I have illustrated a type of filter in which the leaves 120 are adapted to be' mounted upon; the center le points about on theleaf are mounted lat-' 11g cup-shaped members '122, which are .rigid y secured to the leaf in any suitableunanner. In the filtration of many gummy or stickly substances, such as syrup, elatine, glucose,. varnish, and .the like, I dit desirable to mix with the substance to'be filtered some insoluble granular material, such as sand. This may either be used alone or in connection withkieselguhr,

the 11periphe era y exten and has two purposes, first, to make it possible to use a fairly coarse metallic filter medium, and second, to cause the production I of a granular filter cake instead. of a more compact slimy filter cake.

However, whensand orthe like is so used, it tends to set-J 'tle rapidly to the bottom and will not re- .mainin suspension in the slud e," unless some suitable means 1s provided oragitat ing it. In filters of the rotary type, this agitation maybe produced by the cups or paddles-122 attached to the filter leave s. Not only will the rotation of the leaf pro-' .duce the agitation of the sludge or liquid being filtered, but the sand which is actual- .ly caught and retained in the cup upon its upward -travel, "w'ill be discharged as the cup reaches-thetopmost part of theleaf, and it will thus be distributed over the face of the. leaf good. I c Figure 21 illustrates a modified form of agitator in which the filter leaves 120 are connected by blades or paddles 123- which are preferably bolted tothe endor terminal leaves and. which are cut away at 124 to admit the-edges'of' the intermediate leaves, which they thereby support in a direction It will thus be seenperpendicular to their surface and thus hold proper spaced relation. The

inside of the filter-casing as the leaves-'rerubber strips' on a revolv- -volve', such as the withtthe casing in which 4 ing door contact the door is setr quently not trulycircular, but presents small inequalitiesin the'surface. The rubber. strips accommodate themselves tov these in a position" to do the most- It will be appreciated that the castingwhi'ch forms the casingis fre-.

inequalities and insure a continuous contact between the paddles of which they form a part, and the paddles tion and the actual scraping of the casing, kee

at t e bottom. Figures type. of construction in which the. filter leaves 126. are supported upon lateral drainiage pipes 127 and 128 upon Whichlthey are -mounted by a fitting consisting of a See- I tion-129secured to'the leaf, and a section 130 hin ed to the section 129 at 131. The free en be clamped to the-section 129- in any suitable'way', as b means of the bolts .132, thereby firmly c ampin'g the leaf to the pipe. Thesec'tion 129 is provided with 'a drainage channel' 133. communicating at one end; withthe interior of the leaf, and at the f other end with-a nip lo 134 entering the drainage pipe. A- gas the casing. I Like the cups 122', are Well adapted to agitatethe. filtered and through this .agita-l 22, 23 and 24 show a modified of the section 130' is adapted to;

the sand from settling permanently f et 135 may be] used for insuring a water tight joint between the nipple and the drainage channel. At each end the pipes'127 and128 are led to a header 136 connecting with apipe .137, which is rotatably mounted in the casing in the same manner as are the center drainage pipes previously described. In removing the leaf from the drainage pipes, it is merely necessary to loosen the bolts 1'32 and to' swing back the clamfp sections 130, whereupon the leaf will be reed from the pipes.

In order to attain the advantages of the 'lateral supporting leaf andstill'attain the maximum drainage area,'"ll may form a leaf [as shown in Figures and 26, in which.

the greater part of the leaf 138 in formed of a diameter just sufficient to be received in the casing. The leaf is cut away at. 139

and 140 so that it may be slipped laterally over the drainage pipes 127 and 128. Suit- Erble clamps are providedffor securing the eaf tot-he pipes,-each clamp consisting of a section 141 secured to the leaf and a section 142 hinged to the other section at 143,

and having its free end detachably bolted to it at 144. The drainage channel 145 'leads from the interior of the leaf to the nipple 134. .The free end of thesection 142- is forked at 146, so'as to span the adjac'ent art of the binding strip 147.

While lhave illustrated and described only certainspecific embodiments of my invention I realize that it is susce tible of wide a aptation and I do not desire to be limited to the precise construction shown and described nor to the application of certain of the features of my invention to filters of the rotary type, since they are. equalg'applicableto many well-known types of ters.

' claim:-

L'ln a ressure filter, a closed casing, a

' rotatable rainage pipe mounted iii said caspipe, and means for applyingcompression ing, a plurality of separable filter leaves mounted on said pipe, spacing members located between the leaves and spaced from the pipe, a nd compressible means spaced from the pipe and adapted to form a fluidti'ght joint between the leaves and the spacing members, the leaves andspacing members being 'slidable with referenceto the to an assembly'of leaves, spacln members and compressible means, for 100 111g them on the pipe.

'2. In a dpressure filter, a closed casing, a rotatable rainage pipe mounted in said casing, a plurality of separable filter leaves mounte on said pipe, spacing members located between the leaves and spaced from the pi e, and compressible means spaced from t e pipe and. adapted to form a fluidtightjoint between. the leaves and the spacmg members the leaves and spacing memhere being slidable with reference to the mounte located between the leaves and-spaced from the pipe, and compressible means spaced Having thus disclosed my invention, 1

I t rones from the pipe and adapted to forma fluidtight joint between the leaves and the spacing members, the leaves and spacing members being slidable with reference I to the pipe, and a plurality of stops adjustably disposed on said pipe for engaging the terminal leaves ofan assembly of leaves, spacing members and compressible means, for clamping' the saine to the pipe but spaced tr ansversely therefrom.

4c. In a filter, a casing, a filter elementrotatably mounted therein, and automatic means for moving a flat stream of cleansing fluid across the face of'said element and in a substantially parallel planethereto while the element is in motion.

5. lln a filter, a casing, a filter elementrotatably mounted therein, and automatic means for moving a flat stream of cleansing fluid across the face of said element in a plane substantially .parallel thereto while the element is in motion and at a rate of speed proportionate to the speed of said element.

tea

6. In a filter, a casing, afilter element rotatably mounted therein, automatic means for moving a flat stream of cleansin fluid across the face of said element and su stantially parallel thereto while the element is in motion, and means for returning said stream ,to its initial: position.

7. In a filter, a casing, a filter element rotatably mounted therein, means for movlng a flat stream of cleansingfiuid across the face-of said element and substantially parallel thereto while the element is inmotion and at a rate of speed proportionate to the speed of said element and means for re turning said stream to its initial position.

8. In a filter, a casing, a filter element rotatably mounted therein,.means for mov-: ing a flat stream of cleansing fluid across the face of said elementand substantially parallel thereto while the element is in motion and at a rate of speed proportionate tothe speed of said element and means for re-- turning said'stream to its initial position at: a greater relative speed;

9. In a filter, a casing, a filter element movably mounted therein, a sluicing device movably mounted within the casing, a-slowadvance andquick-return device for actuatfl ing said sluicingdevice, and means connectlltl rec

'ing the Said actuating'device vvith the filter element for causing the same to operate in unison.

i '10./ In a filter, a casing, a filterv element- 5 movably mounted therein, asluieing device movably mounted insaid casing, a cam for actuating 'said-sluicing device, to produce a separating action between the said filter ele- -ment-and materialid e osited thereon, and

10 meansfor driving sai c'am from said filter 'lement. i

,11, In a .fi lter, a-i-veasing, a filter element movably mounted'therei'ma slui'cing device 'movafbly mounted.vvitl'iinthe'casing, a foli5 lower interposedb'et'wee'n said earn and said sluicing device, said cainbeing adapted to transmit a slow-advance and quick-return movably mounted therein, asluicing device movably niounted within the ca'sing,'a cam, a follower interposed between sald cam and said sluieing device,,said ram being adapted to transmitaslow-advance and quick-return motion to, said follower, and gearing connecting said earn witirsuid filter element.

ERNECTVJ;SWEETLA-ND 

